Abstract: A plasma treatment apparatus has a reaction vessel (11) provided with a top electrode (13) and a bottom electrode (14), and the first electrode is supplied with a VHF band high frequency power from a VHF band high frequency power source (32), while the bottom electrode on which a substrate (12) is loaded and is moved by a vertical movement mechanism. The plasma treatment system has a controller (36) which, at the time of a cleaning process after forming a film on the substrate (12), controls a vertical movement mechanism to move the bottom electrode to narrow the gap between the top electrode and bottom electrode and form a narrow space and starts cleaning by a predetermined high density plasma in that narrow space. In the cleaning process, step cleaning is performed. Due to this, the efficiency of utilization of the cleaning gas is increased, the amount of exhaust gas is cut, and the cleaning speed is raised. Further, the amount of the process gas used is cut and the process cost is reduced.

Abstract: An ionic liquid of the present invention is “an ionic liquid comprising an organic substance represented by the following general formula (1) as a cation component” and “an ionic liquid comprising a cation component and an anion component, and the cation component is one or plural kinds selected from the group consisting of cation components represented by the following formula (1)”.

Abstract: This invention provides an Mg-based ferrite having a high dielectric breakdown voltage and a saturation magnetization suitable for electrophotographic development, a carrier containing the ferrite, and an electrophotographic developer containing the carrier. The Mg-based ferrite material of this invention comprises Li, Na, K, Rb, Cs, Ca, Sr, Ba, Y, La, Ti, Zr, Hf, V, Nb, Ta, Al, Ga, Si, Ge, P, Sb, Bi or a combination thereof. The Mg-based ferrite material has a saturation magnetization of 30 to 80 emu/g, and a dielectric breakdown voltage of 1.5 to 5.0 kV. The Mg-based ferrite material can realize high image quality, and be in compliance with environmental regulations.

Abstract: This invention provides an Mg-based ferrite carrier composed of an environment-friendly material meeting environmental regulations, and an electrophotographic developer comprising the carrier. The carrier and the developer of this invention realize high image quality and improved gradation properties. This invention also provides a method for producing the Mg-based ferrite material having a saturation magnetization of from 30 to 80 emu/g and a dielectric breakdown voltage of from 1.0 to 5.0 kV, and having the composition of the formula (1). The above properties are obtained by controlling conditions of sintering and heating treatments. CaaMgbFecOd (1) wherein a, b, and c satisfy 0.10 b/(b+c/2) 0.85 and 0 R(Ca) 0.10; R(Ca) is expressed as R(Ca)=a˜Fw(CaO)/(a˜Fw(CaO)+b˜Fw(MgO)+(c/2)˜Fw(Fc2O3)) (Fw(A): formula weight of A j; and d is determined by oxidation numbers of Ca, Mg and Fe.

Abstract: Ionic liquids exhibit a stable liquid state even at low temperatures and have a good conductivity. The ionic liquids each contain an organic compound represented by the following formula (1) as a cation. In the formula, R1 to R5 may be the same as or different from each other and each represents an H, a halogen, or a C1 to C10 alkyl group, cycloalkyl group, heterocyclic group, aryl group or alkoxyalkyl group; X and Y may be the same as or different from each other and each represents an N or a P; Z represents an S or an O.

Abstract: The process for producing carbonyl fluoride according to the invention is a process for safely and easily producing high-purity carbonyl fluoride having a low content of carbon tetrafluoride, and comprises feeding carbon monoxide and fluorine to a reactor and allowing carbon monoxide to react with fluorine under the conditions of a reactor internal pressure of less than atmospheric pressure.

Abstract: A method for removing harmful substances in a vent gas containing a halogen or halogen compound gas remaining in the pipeline of a cylinder cabinet, which comprises contacting the vent gas with a treating agent comprising an alkaline earth metal compound, an alkali metal compound, zeolite, and a carbonaceous material.

Abstract: This invention provides an Mg-based ferrite having a high dielectric breakdown voltage and a saturation magnetization suitable for electrophotographic development, a carrier containing the ferrite, and an electrophotographic developer containing the carrier. The Mg-based ferrite material of this invention comprises Li, Na, K, Rb, Cs, Ca, Sr, Ba, Y, La, Ti, Zr, Hf, V, Nb, Ta, Al, Ga, Si, Ge, P, Sb, Bi or a combination thereof. The Mg-based ferrite material has a saturation magnetization of 30 to 80 emu/g, and a dielectric breakdown voltage of 1.5 to 5.0 kV. The Mg-based ferrite material can realize high image quality, and be in compliance with environmental regulations.

Abstract: Fluorinated pentacene derivatives, for example, the novel compounds tetradecafluoropentacene, 5,6,7,12,13,14-hexafluoropentacene, 5,7,12,14-tetrafluoropentacene, and 6,13-difluoropentacene, and intermediates therefor are provided. And a method of producing fluorinated pentacene derivatives and intermediates therefor is also provided. Pentacene derivatives fluorinated at desired positions of the pentacene skeleton are obtained by introducing the oxo group, hydroxyl group, or alkoxyl group into the pentacene skeleton followed by fluorination with sulfur tetrafluoride and partial defluorination using a reducing agent.

Abstract: A chamber-cleaning gas and an etching gas used for a silicon-containing film according to the present invention comprise a perfluoro cyclic ether having 2 to 4 carbon atoms which are ether-linked with carbon atoms. The chamber-cleaning gas and the etching gas hardly generate a harmful waste gas, such as CF4, which is one of the causes for global warming so that they are good for environment. Further, they are a non-toxic gas or a volatile liquid, and are easy to use and are excellent in treatment of waste gas. Additionally, the chamber-cleaning gas of the present invention has an excellent cleaning rate.

Abstract: This invention provides an Mg-based ferrite carrier composed of an environment-friendly material meeting environmental regulations, and an electrophotographic developer comprising the carrier. The carrier and the developer of this invention realize high image quality and improved gradation properties. This invention also provides a method for producing the Mg-based ferrite material having a saturation magnetization of from 30 to 80 emu/g and a dielectric breakdown voltage of from 1.0 to 5.0 kV, and having the composition of the formula (1). The above properties are obtained by controlling conditions of sintering and heating treatments. CaaMgbFecOd (1) wherein a, b, and c satisfy 0.10 b/(b+c/2)0.85 and 0 R(Ca) 0.10; R(Ca) is expressed as R(Ca)=a˜Fw(CaO)/(a˜Fw(CaO)+b˜Fw(MgO)+(c/2)˜Fw(Fc2O3))(Fw(A): formula weight of A j; and d is determined by oxidation numbers of Ca, Mg and Fe.

Abstract: A cleaning method for CVD apparatus wherein by-products such as SiO2 and Si3N4 adhered to and deposited on surfaces of the inner wall, electrodes and other parts of a reaction chamber at the stage of film formation can be removed efficiently. Furthermore, the amount of cleaning gas discharged is so small that the influence on environment such as global warming is little and cost reduction can be also attained. After the film formation on a base material surface by the use of CVD apparatus, a fluorinated cleaning gas containing a fluorcompound is converted to plasma by means of a remote plasma generator, and the cleaning gas having been converted to plasma is introduced into a reaction chamber so that any by-products adhered to inner parts of the reaction chamber is removed.

Abstract: Iron oxide powder for an undercoat layer of a coat-type magnetic recording medium having a multilayer structure which comprises cobalt-doped iron oxide particles having an average length of 0.02 to 0.3 ?m, an aspect ratio (length to width ratio) of 2 to 13, and a BET specific surface area of 40 to 100 m2/g and containing a cobalt compound in an amount of 0.2 to 10 atom % in terms of cobalt based on total iron.

Abstract: Iron oxide powder for an undercoat layer of a coat-type magnetic recording medium having a multilayer structure which comprises cobalt-doped iron oxide particles having an average length of 0.02 to 0.3 ?m, an aspect ratio (length to width ratio) of 2 to 13, and a BET specific surface area of 40 to 100 m2/g, containing a cobalt compound in an amount of 0.2 to 10 atom % in terms of cobalt based on total iron, and having a pH of 6 to 8, a soluble cation content of 50 ppm or less, and a soluble anion content of 50 ppm or less.

Abstract: The first chamber cleaning gas and the first silicon-containing film-etching gas of the present invention comprise at least one compound selected from the group consisting of FCOF, CF3OCOF and CF3OCF2OCOF, and O2 in the specific amount, and optionally other gases. The second chamber cleaning gas and the second silicon-containing film-etching gas comprise CF3COF, C3F7COF or CF2(COF)2 and O2 in specific amounts, and optionally may comprise other gases. The chamber cleaning gases and silicon-containing film etching gases of the present invention have a low global warming potential and hardly generate substances in the exhaust gases such as CF4, etc, which are harmful to the environment and have been perceived as contributing to global warming. Therefore, the gases are friendly to the global environment, and have easy handling and excellent exhaust gas treating properties. Further, the chamber cleaning gases of the invention have excellent cleaning rate.

Abstract: A waste gas stream containing toxic NF.sub.3 and optionally other gases, such as acidic fluoride gases, for example, HF, SiF.sub.4, MoF.sub.6 and WF.sub.6 is first treated with particles or ribbons of a Cr-containing Fe alloy at about 300-600.degree. C. to remove the NF.sub.

Abstract: A waste gas stream containing toxic NF.sub.3 and optionally other gases, such as acidic fluoride gases, for example, HF, SiF.sub.4, MoF.sub.6 and WF.sub.6 is first treated with particles or ribbons of a Cr-containing Fe alloy at about 300.degree.-600.degree. C. to remove the NF.sub.3 content and, if desired, subsequently with an alkaline neutralizing agent in the form of pellets to remove the acidic fluoride contents, if any; said alloy containing preferably about 16-26% Cr and being used in a form of bed packed with said ribbons.

Abstract: A novel carrier material useful in conjunction with a toner for preparing a two-component developer for electrophotographic processes is provided. The carrier comprises a spherical magnetite particulate material having a reduced metallic iron outer layer which is coated with an outermost resinous layer for conditioning the copying properties of the carrier.

Abstract: A novel carrier material useful in conjunction with a toner for preparing a two-component developer for electrophotographic processes is provided. The carrier comprises a spherical magnetite particulate material having a reduced metallic iron outer layer which is coated with an outermost resinous layer for conditioning the copying properties of the carrier.

Abstract: A noval carrier powder for electrophotographic developers is provided. The carrier powder comprises spherical magnetite particles having a wustite (FeO) content of less than 10% by weight, a particle diameter of 30-200 .mu.m and a surface porosity of less than 20%.